Diaphragm assembly and method of making same



June 16, 1953 J. M. BARR 2,642,090

DIAPHRAGM ASSEMBLY AND METHOD OF MAKING SAME Filed Nov. 16, 1946 INVENTOR. John M. Barr AGENT lphragm is allowed to dry,

Patented June 16, 1953 DIAPHRAGM ASSEMBLY AND METHOD OF MAKING SAME John M. Barr,

West Hartford, Conn., assignor, by

mesne assignments, to Niles-Bement-Pond Company, West Hartford, Conn., a corporation of New Jersey Application November 12 Claims.

The present invention relates to methods of forming pressure responsive diaphragm structures, and particularlyto forming such structures which are intended to be used in contact with a liquid and also to the diaphragm assembly produced by the method.

16, 1946, Serial No. 710,346

" Diaphragm structures of the type to which my invention relates generally consist of a fiat central circular portion and a fiat annular peripheral portion, separated by a deep convolution.

It is common to provide rigid reinforcing members for the opposite sides of the flat portions of the diaphragm. These rigid members are attached to the diaphragm by bonding, clamping, or any other suitable method. The diaphragm itself is usually formed of a suitable base, usually fabric, impregnated with rubber or some similar material, although the fabric is sometimes omitted and rubber alone used. Where the word rubber is used in this specification and claims, it is intended to be generic to rubber andall other similar materials.

It is customary, in assemblying these diaphragm structures, to attach the rigid reinforcing members to the diaphragm when it is in a dry condition. When the diaphragm is placed in use, in contact with a liquid, the liquid may cause distortion of the convolution. This has been found to be especially true where the liquid is one of the hydrocarbons, such as are commonly used as fuels for internal combustion engines. It has been found that such fuels cause the rubher in the diaphragm to swell, thereby changing Some fuels actually leach in the rubber. In such the diaphragm shape. out part of theplastic'izer cases the fuel acts as a plasticizer as long as itremains in contact with the rubber. This change in plasticizers results in a general swelling and distorting of the rubber. If such a diait becomes somewhat stiff, and must be soaked in fuel before being placed in service again. In some cases, the fibers of the fabric may also be distorted when they are in contact with the fuel. tions of the diaphragm are rigidly clamped in place and cannot move, while the diaphragm convolution is relatively free to change its shape, stresses are set up in the diaphragm because of its distortion.

It is an object of the presentinvention to provide a method of forming diaphragms for use in contact with liquid, which'will prevent stressing of the diaphragm when placed in service because of distortion due to the action of the liquid on the diaphragm.

Since the fiat por-v sembled with the reinforcing Another object of the present invention is to provide an improved method of assembling a fabric diaphragm with rigid reinforcing members.

Other objects and advantages of the present invention will become apparent from a consideration of the appended specification, claims and drawings, in which Figure 1 represents a cross-sectional view of a fabric diaphragm to be assembled in accordance with my invention,

Figure 2 is a cross-sectional view of a set of reinforcingmembers to be assembled with the diaphragm of Figure 1 in accordance with my invention,

Figure 3 illustrates the soaking of the diaphragm of Figure 1 in the liquid which it is to contact in service, this soaking being an essential step in my invention,

Figure 4 shows the soaked diaphragm asmembers of Figure 2, and I Figure 5 shows the assembled diaphragm and reinforcing members after the diaphragm has dried.

Referring to the drawings, there is shown in Figure l a diaphragm, generally indicated at It), which may be used in the practice of my invention. The diaphragm It) consists of a central circular portion 52, a peripheral annular portion l4, separated by a convolution E6. The diaphragm I0 is usuaily formed of fabric suitably impregnated with rubber or some similarmaterial. The convolution may be formed in'the rubberized fabric according to any of several well-known processes. I

FigureZ illustrates a pair bers I8 and 20, which are adapted to be placed on opposite sides of the central circular portion 12 of the diaphragm it] of Figure l and a pair of annular reinforcing members 22 and 24, which are adapted to be placed on opposite sides of the annular portion M of the diaphragm I0. 4

In accordance with my invention, before assembling the diaphragm It with the reinforcing members, I first soak the diaphragm in the-liquid which it is to contact when placed in service. This step'in the assembly process is illustrated in Figure 3, wherein the diaphragm I0 is placed in a'ta'nk ,26 filled with a liquid 28 deep enough to completely cover the diaphragm l8.

After the diaphragm has soaked in the liquid long enough to absorb the liquid and swell to the shape it' will assume in use, the diaphragm is removed from the liquid and assembled'with of reinforcing memthe reinforcing plates, as illustrated in Figure 4. This assembly takes place while the diaphragm is still substantially saturated with the liquid, although it is permissible to allow the surface to dry before assembly.

Figure 5 illustrates the form which the convolution of the diaphragm may assume if it is allowed to dry after being assembled, as illustrated in Figure 4. It should be noted that the sides of the convolution in Figure 5 are separated from the reinforcing plates. It does no harm to store or ship the dry diaphragm assembly with the convolution separated from the reinforcing plates. The convolution also may appear, at this time, to be rough and distorted. This, too, will not affect the operation of the diaphragm. When the diaphragm is finally placed in service and again in contact with the liquid in which it was soaked, it will again assume the shape it had in Figure 4 and it will again fit the reinforcing members. 7

The terms and expressions which I have employed are used as terms of description and not of limitation, and I have no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within th scope of the invention claimed.

I claim as my invention:

1. A pressure responsive diaphragm assembly for use in contact with a liquid fuel for internal combustion engines, comprising a thin, highly flexible rubber-impregnated fabric diaphragm preformed with a relatively deep convolution and soaked in the liquid which it is to contact in use and allowed to swell and otherwise assume the contour it will have in use, a pair of rigid reinforcing discs attached to the opposite sides of a central circular portion of said diaphragm, and a pair of rigid reinforcing annular members attached to a peripheral annular portion of said diaphragm spaced from said central portion while said diaphragm is still substantially saturated with said liquid, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid.

2. The method of constructing a flexible diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising the steps of soaking in said liquid a thin, highly flexible, preformed, rubber-containing diaphragm consisting of aflat, central, circular portion and a flat, annular peripheral portion, joined by a deep convolution, clamping each of said fiat portions of said diaphragm between spaced, rigid reinforcing members while it is still substantially saturated with said liquid, and drying said assembly of diaphragm and reinforcing members, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid.

3. The method of constructing a flexible diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising the steps of soaking in said liquid a thin, highly flexible, preformed diaphragm consisting partly of rubber and having a flat, central, circular portion and a flat, annular peripheral portion, joined by a deep convolution, clamping a pair of spaced, rigid members to each of said flat portions of said diaphragm while it is still substantially saturated with said liquid, and drying said assembly of diaphragm and rigid members, so that said diaphragm will not be stressed when 4 placed in service by deformation thereof due to wetting with said liquid.-

4. The method of constructing a flexible diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising the steps of soaking in said liquid a thin, highly flexible, rubber-containing diaphragm having a flat, central, circular portion and a flat, annular peripheral portion, joined by a deep convolution, clamping to each of said flat portions of said iaphragm a pair of rigid reinforcing members on opposite sides of said diaphragm while said diaphragm is still wet with said liquid, and drying said assembly of diaphragm and reinforcing members, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid.

5, The method of constructing a flexible, pressure-responsive diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising the steps of soaking in said liquid a thin, highly flexible, rubber-im-' pregnated fabric diaphragm, having a flat, central, circular portion and a flat, annular peripheral portion, joined by a deep convolution, allowing said diaphragm to swell and otherwise assume the contour it will have in use, clamping a pair of rigid reinforcing discs to the opposite sides of said central portion of said diaphragm and a pair of rigid reinforcing annular members to the entire periphera1 annular portion of said diaphragm spaced from said central portion by said convolution, while said diaphragm is still substantially saturated with said liquid, and drying said assembly of diaphragm and reinforcing members, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid.

6. The method of constructing a flexible diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising the steps of soaking in said liquid a thin, highly flexible, rubber-containing diaphragm having a fiat, central circular portion and a flat, annular peripheral portion, joined by a deep convolution, clamping at least one rigid reinforcing member to each of said flat portions of said diaphragm while it is still substantially saturated with said liquid, and drying said assembly of diaphragm and reinforcing members, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid.

7. The method of constructing a flexible, pressure-responsive diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising the steps of soaking in said liquid a thin, highly flexible, rubber-impregnated fabric diaphragm having a fiat, central, circular portion and a flat, annular periphera1 portion,,

joined by a deep convolution, allowing said diaphragm to swell and otherwise assume the contour it will have in use, and clamping at least one rigid reinforcing member to each of said flat portions of said diaphragm while it is still substantially saturated with said liquid, and drying said assembly of diaphragm and reinforcing members, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid.

8. A flexible diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising a pair of spaced rigid members connected by a thin, highly flexible, rubbercontaining diaphragm having a flat, central circular portion and a fiat, annular peripheral portion joined by a preformed, relatively deep convolution, said diaphragm being first soaked in the liquid which it is to contact infuse, then clamped at both of its said flatportions be tween said reinforcing members while still substantially saturated with said liquid, and dried in a'ssembled condition, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid. r

9. A diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines,

comprising a pair of spaced rigid members and a thin, highly flexible member, consisting of at least partly of rubber, connecting said rigid members, said flexible member consisting of a thin diaphragm having a flat, central circular portion and a flat annular peripheral portion joined by a preformed, relatively deep convolution, said diaphragm being first soaked in said liquid, and then having each of its said flat portions clamped to one of said rigid members while said diaphragm is still substantially saturated with said liquid, and dried in assembled condition, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid.

10. A diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising a pair of spaced rigid reinforcing members connected by a thin, highly flexible rubber-containing diaphragm having a flat, central circular portion and a fiat annular peripheral portion joined by a preformed, relatively deep convolution, said diaphragm being first soaked in said liquid and then clamped at each of its said flat portions to one of spaced rigid reinforcing members on opposite sides of said convolutions while said diaphragm is still wet with said liquid, and dried in assembled condition, so that said diaphragm will not be stressed When placed in service by deformation thereof due to wetting with said liquid.

11. A diaphragm assembly, for use in contact with a liquid fuel for internal combustion engines, comprising a plurality of spaced, rigid reinforcing members connected by a thin, highly flexible rubber-containing diaphragm having a flat, central circular portion and a flat annular peripheral portion joined by a preformed, relatively deep convolution, said diaphragm being first soaked in said liquid, then attached to said rigid members, by clamping each of said fiat portions to one rigid reinforcing member, while said diaphragm is still substantially saturated with said liquid, and dried in assembled condition, so that said diaphragm will not be stressed when placed in service by deformation thereof due to wetting with said liquid.

12. A pressure-responsive diaphragm assembly, for use in'contact with a liquid fuel for internal cornbustionengines, comprising a pair of spaced, rigid reinforcing members connected by a thin, highly flexible, rubber-impregnated fabric diaphragmhaving a flat, central circular portion 1 and a flat annular peripheral portion joined by a preformed, relatively deep convolution, said diaphragm being first soaked in said liquid and allowed to swell and otherwise assume the contour it will have in use, then having each of its said flat portions clamped to one rigid reinforcing member while it is still substantially saturated with said liquid, and dried in assembled position,

so that said diaphragm will not be stressed when placed in service by deformation due to wetting.

JOHN M. BARR.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,851,553 Walker Mar. 29, 1932 2,129,289 Sell Sept. 6, 1938 2,170,919 Thener Aug. 29, 1939 2,250,674 McBurney July 29, 1941 2,293,266 Mitchell Aug. 18, 1942 

